Phillip does not bother to respond, or perhaps he merely doesn't have time to as he's pressed up against the wall and taken down so quickly. He lets out a low hiss and tightens his fingers in the other's hair, clearly a way to just release the pressure inside of him than any indication of pain. He has no obvious way to muffle himself, after all.

Still, what might get more of Gustavain's attention and certainly what is more surprising is that Phillip doesn't push back against the control, lets him have it and seems to fall into it. As long as they've known each other, Phillip's never been particularly comfortable with vulnerability, possibly even less so since they've reconnected and Gustavain figured out what he was. He hasn't really been different, and it's possible it just hasn't come up, but there's definitely a moment where his hand slips from Gus's hair and laces into one of his. The trust between them, at least, doesn't run just one way.